The present invention relates to the technical field of sealing slide fasteners, in other words those made in such a way as to prevent the passage of fluids, even if put under pressure within predetermined limits.
A fastener of this type, as is known, comprises two tapes of elastic material with their edges facing each other, which are pressed together in such a way as to make them provide the desired seal as a result of the coupling of two sets of aligned teeth caused by the passage of a closing slider.
These teeth are fixed to the tapes by various systems, of which one, for example, is described in the patent U.S. Pat. No. 2,910,745, and another is described in the patent GB-A-2,047,334.
The latter document describes the system most commonly used in the present state of the art to fix the said teeth on the tapes which they are to join, this system consisting in forming the teeth in two halves, interposing between them the edges of the tapes which are to be joined, and joining the said two halves together and to the tapes by mechanical connecting means which perforate the tapes.
This solution is complicated and expensive to implement, and cannot guarantee an effective tightness of the slide fastener, since a liquid, whether under pressure or not, can easily infiltrate through the holes through which the mechanical connecting means—usually male/female connectors—pass.